磁性复合载体固定生姜蛋白酶的工艺优化研究

Study on Optimization of Immobilization of Ginger Protease with Magnetic Composite Carrier

文章以生姜为原料,首次采用海藻酸钠和明胶包埋Fe3O4以得到凝胶微球载体,利用Box-Behnken响应面分析法对磁性复合载体固定化生姜蛋白酶的工艺进行优化。在单因素试验结果的基础上,以固定化生姜蛋白酶酶活力为响应值,利用响应面分析法研究各因素及其交互作用对固定生姜蛋白酶效果的影响,建立预测模型,确定最佳工艺条件。结果表明:磁性复合载体固定生姜蛋白酶的最佳条件为:Fe^2+∶Fe^3+体积比为0.75∶1,磁核量Fe3O4为3.0 mg/mL,海藻酸钠与明胶体积比为2∶1,戊二醛浓度为3%,交联时间为1.5 h,固定时间为60 min,pH值为4.4,酶量为30 mg/g载体。该条件下固定化酶活力的预测值为50.39 U/g,然后进行3次平行验证试验,得到固定化生姜蛋白酶的活力为52.63 U/g,与预测值接近,证明了此模型的合理性。

In this paper,ginger is used as the raw material.Fe3O4 is embedded by sodium alginate and gelatin for the first time.The gel microsphere carrier is obtained.The Box-Behnken response surface analysis is used to optimize the immobilization process of magnetic composite carrier on ginger protease.On the basis of single factor test results,taking the activity of immobilized ginger protease as the response value,the effects of various factors and their interaction on the immobilization of ginger protease are studied by response surface analysis(RSA),the prediction model is established and the optimum technological conditions are determined.The results show that the optimum conditions for immobilization of ginger protease with magnetic composite carrier are as follows:the volume ratio of Fe^2+∶Fe^3+is 0.75∶1,the magnetic nucleus quantity of Fe3O4 is 3.0 mg/mL,the volume ratio of sodium alginate to gelatin is 2∶1,the concentration of glutaraldehyde is 3%,the crosslinking time is 1.5 h,the immobilization time is 60 min,the pH value is 4.4,the enzyme amount is 30 mg/g carrier.The predicted activity of immobilized ginger protease under such conditions is 50.39 U/g.After three times'parallel validation experiments,the activity of immobilized ginger protease is 52.63 U/g,which is close to the predicted value and proves the rationality of this model.